Duodenal lymphocytosis in functional dyspepsia

Background and study aims: Functional dyspepsia is an exclusion diagnosis requiring different tests, including endoscopy, often repeated over time. Duodenal biopsies are frequently resorted to, not rarely revealing duodenal microscopic inflammation. Aim of the study is to confirm a previously supposed role of antro-duodenal low-grade inflammation in functional dyspepsia, evaluating the frequency of duodenal lymphocytosis, H. pylori infection and their association in a group of patients with functional dyspepsia compared to asymptomatic control subjects. Patients and methods: A cross-sectional, observational study has been conducted screening all the patients who underwent duodenal biopsies during upper endoscopy, in a 30 months period. All the patients without endoscopic lesions were analysed. The study group consisted of patients compatible with the diagnosis of functional dyspepsia (Rome III criteria). The control group consisted of healthy asymptomatic subjects in the population subjected to endoscopy. The presence of duodenal lymphocytosis and of H. pylori infection in the two groups was evaluated. Results: 216 patients were enrolled: 161 in the functional dyspepsia group and 55 as asymptomatic control group. The frequency of duodenal lymphocytosis was similar between cases and control groups (25.47% vs 25.45%; p = 0.99), as well as H. pylori infection (26.71% vs 23.64%; p = 0.78). Duodenal lymphocytosis was significantly associated with functional dyspepsia only in H. pylori positive dyspeptic patients (p = 0.047). 94% of the subjects with both lymphocytosis and H. pylori infection suffer from dyspepsia. Duodenal intraepithelial lymphocytosis is significantly associated with bloating (p = 0.0082). Conclusions: In our cohort of dyspeptic patients, duodenal lymphocytosis is significantly associated with bloating and the simultaneous presence of duodenal lymphocytosis and H. pylori infection is significantly more prevalent than in control subjects.